Since SSDI benefits are based on your work record, they are generally comparable to your Social Security retirement benefit, had you been able to work until retirement. If you know your entire earnings history, you can input it into this calculator in order to get an estimate of what your disability benefit would be.
Better yet, the easiest way to get an idea of what your disability benefits could be, as well as whether or not you’re eligible, is to create an account on www.ssa.gov and view your most recent Social Security statement. You can find this information, as well as lots of other useful information about other potential Social Security benefits to which you may be entitled.
As you can see from the sample Social Security statement above, this individual has worked enough to qualify for disability benefits, and their projected monthly benefit of $1,596 is in the ballpark of their expected retirement benefit of $1,762.
If you become disabled and can no longer work, you may qualify for Social Security Disability Insurance (SSDI) based on your work record. Since SSDI benefits are based on your work record, they are generally comparable to what your Social Security retirement benefit would have been, had you worked until retirement age. Here’s what you need to know about whether you qualify for SSDI and how to determine what your benefits could be.
More info here:http://www.fool.com/retirement/general/2016/05/22/what-benefits-do-you-get-from-social-security-disa.aspx